<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script src="https://unpkg.com/vue@next"></script>
<div id="app">
    <input type="radio" v-model="pick" :value="a">
    <!-- 会把pick改成a的值 -->
    <span>pick:{{pick}} a:{{a}}</span>
</div>
<script>
    const vueOpt = {
        data() {
            return {
                pick: '1',
                a: ''
            }
        }
    }

    Vue.createApp(vueOpt).mount('#app');
</script>
</body>
</html>
